The present invention is directed to therapeutic methods using IL-6 antagonists such as anti-IL-6 antibodies and fragments thereof having binding specificity for IL-6 to prevent or treat mucositis (e.g., oral mucositis) including persons on a treatment regimen with a drug or chemotherapy and/or radiation for cancer (e.g., head and neck cancer) that is associated with increased risk of mucositis, including oral mucositis.